Water-tube boiler



Jan. 24, 1928. 1,657,319 J. H. ROHRER WATER TUBE BOILER Filed April 19232 Sheets-Sheet? Z0 3 1 m f J9- Patented 24, 192.8.

JOSIAH HQ RQHBER, OE PHILADELPHIA, PENNSYLVANIA.

XVATER-IUBE BOILER.

Application filed April 2, 1923.

My invention relates to boilers of the water-tube typeand particularlyto the providing of such boilers with a teed-water heater so constructedand arranged that the deleterious or corrosive gases, contained in theteed-water and liberated therefrom by the heating thereof, are nottrapped, re tained or confined for any substantial length of time in anyone part of the entire boiler structure, nor in the feedwvater heater,but are discharged thereiroinsubstantially as test as they are liberatedfrom the feedwater, with the result that the life of all the sections ofthe boiler is greatly prolonged.

in watentubc boilers it is common prac tire to introduce the Steed-waterfor the boiler directly into the economizer section, and unless thefeed-water has been treated prior to its admission into the economizersection to expel the gases therefrom, those gases accun'iulate at thetop of the economizer-secl'ion and reu'iain there so long that theycorrode the interior of the economizer.

' ihe gases are usually trapped in the upper drum of the (BCOHOHllZQI.One of the objects of this invention is to transfer heat from theeconominor-section or": a boiler to the feedwater pipe and to dischargethe teed-water so heated directly into the steam-generatingsection asdistinguished from discharging it directly into the economizer-sectionso that the deleterious gases, dissolved in or carried by the teed-waterimmediately rise with the s am being generated in the steam-generatiection. to the top of the steam-generat ing-section of the boiler.whence they are dicharged troni the boiler with the steam substantiallyas fast as they and the steam are generator. with the. result that thedeleterious gases have no time or opportunity to remain long enough incontact with an particularpart of the interior of the boiler toinjuriously affect the boiler structure. y Y

A iturtl'icrobjcct of my invention is to maintain the water in theeconomizer-section at a corn-iderahly lower temperature theeconomizensec Serial No. 629,332.

'ater, freed from the deleterious gases, from thesteaingenerating-section of the boiler.

Other objects of my invention will appear in the specification andclaims below.-*

In the drawings forming a part of this specification and in which thesame reference characters are employed throughout the various views todesignate the sameparts, 1 is a vertical longitudinal secw tional viewof a water-tubeboiler provided with my invention, the boiler structurebeing to a great extent diagrammatic and only such parts being indicatedas directly cooperate with my invention;

Fig. 2 is another diagrammatic view of. the automatic means formaintaining constaut the height of level of water in theeconomizer-section of the boiler, for the purpose of illustrating howaboiler cquipped with my invention operates;

Fig. 3 is a view similar to Fig. Qbut showing the connections formanual, as distinguished from automatic,regulation of the supply ofwater to the economizer-section. 7

Referring first to the invention as illus trated in Fig. l, theboiler-housing or casing .i encloses the steamgenerating-section B an lthe econoniizer-section C. The steamgeneratingscction B v n'eterablycomprises a triangular arrangement of drums,the top drum 1 being thesteam-and-water drum,

the next lower drum 2 being a water-drum,

and the lowest drum 3 being the mud drumn A. bank of water tubes lextends in an 1H:

and the water drum 2. a second bank of tubeso extends upwardly from thewater drum 2 to the steam-ai'id-water drum 1, and a third bank of'tubes6 extends between the steam drum 1 and the mud drum 3. Over the waterdrum 2 and at the top of the casing A. is a header or steam'drum 7connected to the steam-and-water drum 1 by a bank of. tubes 8 by meansof which the steam in its passage from the steam-andwater drum 1 to thesteam drum 7 may be superheated. The tubes 8 are in fact superheatertubes. Over the lower half of the bank of tubes 4i is an inclined bathe9 and a vertical battle 10 and the latter, entering the bank of tubesextends forwardly toward the water drum 2. Over the forward end of thebank of tubes 5 is baffle 11. Midway of the bank of tubes 6 andextending down: wardly from the stean1-andwater drum 1 clined directionbetween the mud drum 3 is a bathe 12. Disposed between the bank of tubes6 and the 6601101111201 C is a vertical bafiie 18.

The hot gasesoi combustion 11550110111 the fire-box 1 1 and travellongitudinally oil' the bank of tubes l, directed by the iutlined bailie9, and then pass substantially vertical- 1y through said bank of tubesel and through the bank 01. tubes 5. They are then deflected bythebattle 11 'longitiulinally oi the bank 5 and into the space between thedrums 1. and

a 7, and over and around the auperheater tubes 8. Thence the gases passdownwardly through the bank of tubes Sbetween the bailles 10 and 12,heating substantially onehalf ofthe bankot tubes 6 in their downwardpassage. Passing; around the lower end of the baffle 12 and through saidbank of tubes, the ases thenrise vertically between the baffle 12 andthe bathe 13 where they enter the econoininor-section C of the boiler.So far as has beenabove described,

the boiler may bound is of usual construc the boilerhousing A and thenoutthrough the stack 5. i

To supply feed water to the boiler I provide a pipe 19 which may beprovided with any suitable valve 20 to control, admit and ch eel: thewater allowed to flow therethrough.

This tube or pipe 19 passes through the wall of the upper'econoinizerdrum 1.5 and iscon nectedto a coil or radiator 21 within the upper druin15. The other end of the radiator 21 is connected to a pipe 22 which,

nassin downwardly from the 11 men econol a e .i l i niizer drum 15 ispreferably connected to and discharges into the lower drum 3. Conmeetingthestea n and-water drum 1 with the upper druin 15of theecononiizer-section C is a pipe 23-23 in which is an automatic valve Dwhich may be ofany wellknown automatic iteed-water-regulating type. Itsoperation will he described more particus I larly below. The pipe 23should enter the steam-andwater drum 1 below the waterlevelythereof, sotht'lt when the valve D is open water from the steam-and-water drurnlflwillflow intothe upper drum 15 of: the econonii zer-section G.Outside of the boiler structure A and adjacent and in front of theupperdrum 15 of the econoinizeu is a gageeock E, when maybe oi usualconstruction Attached to the gage-cook is a regulator or controllef F,the upper end of whichis connected by a pipe 27 with the upper part oi.the gage-cock E (and thus to the steam space in the drain 15)., thelower end of which is similarly connected by a pipe 28 with the lowerend of the gage-coclrl l (and thus with the water in the drum 15).

Referring now to Fig. 2 for a n'iore detailed but somewhat diagrammaticview of the controller or regulator F and the valve D, the regulator Fconsists oi. the shell 29; preferably substantially cylindrical 111shape,

having its upper end connectedby the pipe 27 in any suitable way withthe space above the water level in the drum 15 and its lower endconnected by the pipe 28 with the water in the drum 15. Extendinglongitudinally of the casing 29 is atube 230 closed at its upper end andextending out through an end or side thereof where it is connected by apiping 31 to a closed casing 32 one side oi? which is covered by adiaphragm 323.

It will be seen from the above that as the level of the water in thedrain 15 rises or lowers, it correspondingly respectively b mergesoruncovers a greater or less length of thepipe 30 within the casing: 29.This pipe 30 is illedwith a liquid which will volatilize-and createpressure under the heat oi? the steam but which will become relativelycooler when covered with the water fronithe drum 15. It is to bereinen'ibered that the water in the econoinizcr, and eonse f uently thatin the casing! 29, is kept relatively cool by the teed-water flowingthere through as will the referred to again below, hen therefore thewater in the drum 15 falls belo a predetermined point more of thecontents of the tube 30 subjected to the heat of the steam, and pressureis created in the pipe 30. Thisprcssure is communicated through the pipe531. to the chamber 32 above the diaphragm 35-3 to depress the diaphragmand the parts (liicl'lltcll thereby.

The valve 1') is preteraliily a nearly balanced valve The constructionis only diagranin'iatieally illustrated in Fina 2, because no claim inthis case is made to the particular construction of this regulating:valieQ it may be of any well know" stain'lard type and therefore abrietdescription will be all that is necessary for a lull understandingofthe This common connection lLliJ operation thereof in connection withapplicants invention. The diaphragm 33 which is carried by and securelyattached to the ca p or chamber 32, is also preferably secured to anysuitable struts or frames 84, the lower end of which rests on and aresecured to and are supported by thecasing 35 of the autoniatic valve D.To the center of the diapln-agni 33 is attached a stem 36 which, passingdownward into and through the casing 35, carries with it a valve 37 anda valve 38 adapted to cooperate with the valve seats 39 and 40respectively.

T he stem 36 preferably extends below the valve 38 and out through thecasing 85. Outside of the casing 35 it is provided with a disk orshoulder 4-1 against which bears the upper end of a coil spring 42, thelower end of which presses against a suitable rigid bracket or support13 secured to the under side of the casing 35. From the aboveit isbelieved that it will be plain that when by reason of an increase of thepressure in the pipe 31, the diaphragm 33 is depressed, that movement ofthe diaphragm will force the valv s 37 and 38 031i their respectiveseats39 and at) and water from the drum 1 will pass through the valve,into the pipe 23 and into the upper drum 15 of the economizersection.lVhen the water has attained a predetermined height in the drum 15, andthe tube SOis covered with water, the pressurein the pipe 31 will fall,and the spring 42 will return the valves 37 and 38 to their respectiveseats to prevent any iurther passage otwater from the drum 1 to the drumThe abovethen provides an automatic means for maintaining atsubstantially a i'lXQCl level the water in the upper drum of theeconomizer, the water being supplied thereto :irom time to time comingdirectly from the generator section of the boiler.

lily invention is, however, not limited solel to the automaticreplenishing of the economizer with water from the boiler. This may beaccomplished manually because the evaporation oi? the water in theeconomizer is very slow under ordinary circumstances. Therefore it isonly necessaryforthe engincer or boiler man to look from time to time atthe sight-glass 241- and i f he finds the water therein at low level andhe observes that the level of the water in the drum 15 has :tallen, hemay manually open a hand valve and admit watertrom thesteam-gei'ieratorsection to the eeonoinizer. Such a modifiedconstruction is illustrated in Fig; 3 wherein the automatic *alve D isreplaced by a manually operable valve DC The above description hashadreterence v to the conveying of feed water through a coil or radiatorin the upper economiZer-drum to the mud drum and the transfer at hotpurified water from the steamgenerating-section B. to theeconomizer-section C through the pipes 23, 28. Of course, the water willnot. fall in the economizer-section unless there has been an evaporationof it. lVhen for any reason the heat of the water in theeeonomizensection is suificient to generate steam (and generallyspeaking there are many installations in which the economizer willmerely provide a means for heating the incoming teed-water withoutgenerating steam) and the pressure above the water level in the drum 15is a little greater than it is in the boiler, such steam will pass fromthe drum 15 to the steanrand-water drum 1 through a check valve G andthence through the pipe a l to the drum 1. This check valve may be ofany ordinary and usual construction permitting of the flow of steamfromthe drum 15 to the drum 1 but preventing the backward flow of waterfrom the drum 1 to the drum 15. a

This feature of construction is important. The substantially continuousflow of cold feed-water through the coil 21 keeps the tem perature ofthe water in the economiZer-seotion C subs antlally lower than that ofthe water 1n the steam-generating-section B.

But if, for any reason, the flow of teed-water should cease, then thetemperature of the water in the economizcr-section will rise and thesaid section C may become a steam-generating-section. The check valve Gand pipe 14 permit the steam so generated in the economizensection to betransferred to the main generatingsection B whenever the pressure in thesection C is substantially equal to that in section B. It'will beapparent that, under these conditions, the valve 1) will be open for thetree passage of water from section B to section C. When, how ever, the.saline conditions arise in the arrangement shown in Fig. 3, the firemanor boiler man will manually open the valve D to keepthe section Csupplied with water a from the section B.

Under some circumstances I may so de-r sign and proportion the parts ofthe boiler that the section B will be operative to gerr erate steam at arelatively high temperature and pressure, and the section C will operateto generate steam at lower ten'iperatures in which case the section 0will be both an economizer-section and a steam-generating section. Insuch an arrangement the steam, accumulating in the drum 15, will flowinto the section B when the pressure in thesecins tion Chas built up tothe pressure in the sectionB. In this arrangement the regulator F willbe so arranged, constructed and operated as to maintain the level of thewater in the section C substantially constant by admitting thereto fromtime to time, through the valve D, water from the section B, as beforedescribed. a

,VVhen the section G is arranged and is type of saf y 111g temperatures,

operative to act merely an economizer and not as a steanrgeneratoigundernormal conditions, that is to say so long as cool feedwater ispassing through the coil 21, the water in the economizer remains substantially constant. As it circulates through the bank of tubes l7 betweenthe drums 15 and 16 it heated by the hot gases of combustion. In thedrum 15 it is cooled by the feed-water in the coil 21. The heat absorbedfrom the hot gases by be water in the section C is transferred to thefeed-water passing; therethrough. Under these conditions only a verysmall amount of Water is required to be transferred thereto from sectionB to maintain constant the level otthe water in the drum 1.5.

The ch ch "alve G- lilie a safety valve in that by it theeconomizensection is relieved oi any accumulation of steam above apredetermined point of pressure. The accumulated steam, thus allowed toescape from the economimar-section, is not lUSiI lLJUiJ-lS dischargedinto the steamgeneratingsection of the boiler. If, however, for anyreason it is not deemed neces sary or advisable to save or utilize thesteam "which may be so generated in the economizer-section, such steammay be allowed to escape to the atmosphere throughany other pop valveconstruction.

lVhen the ope 'ation of the boiler is such that the temperature of theWater in the econoi'nizer-section is normally below steamas the resultof the flow of cold :Eeedavater through thepipe 19 and coil 520, thevolume oi the Water in the econoinizer-section will remain substantiallyconstant. T he Water therein will merely circulate Without substantialevaporation and there will be no occasion to replenish the \vaterin theeconomizer-seetion except at long intervals. In such boilers only alittle Water is added at one ltimeto that in the economizer-section andthat is preferably drawn from the steam-generating-section or from anytime of such added Water will be so small that the volume ol thedeleteriousor corro sive gases containcdtherein is substantiallynegligible. i l-laving thus described my invention, I claim and desireto protect by Letters Patent of theUnitcd States:

l. The combination with a boiler comprising a stinni-generating-sectionand an economizer-section having an upperdrum, of i means tor freeingWater ot deleterious gases and for discharging said gases from theboiler substantially as rapidly as said gases are liberated from thefeed-Water, comprising a feed-waster conduit passing through said drumof said economizer-section and discharging directly into saidsteam-generating-section, and means operatlve when the operatessubstantially other convenient source. The volsupply of feed-Water issubstantially reduced and the steam pressure in said economical:-

section is substantially that of the stea1n boiler to transfergenerating-section of said steam from said economizer section to saidsteam generating section and to deliver feed water to said economizersection from said steam generating section. i i

2. The combination With a boiler eon'iprising a steam-generating-secthinand an econ- ()llllZQE-SEClilOll having a drum o'i' means for freeingfeed-water of deleterious gases and for discharging said gases from theboiler suliistantially as rapidly as said games are liberated from theteed-water, comprising a feed-Water conduit passing through aideeonomizer-section and discharging directly into saidsteanrgenerating-section, means to maintain substantially constant thelevel of the Water in said economizer-section with Water from saidstcam-generating-section, and means to transfer steam at and aboveboiler pressure from said economizer-section to saidsteam-generating-section, whereby any substantial reduction oil thesupply of teed water converts said econoi'nizcr-eection into a itsteam-generating-section and said economizensection is not emptied ofWater.

3. In a boiler comprising a steam-generating-section and ancconomizer-section having an upper drum, the combination therewith ofmeans to prevent the accumulation within the boiler of deleterious gasescon tained in the feed-water,comprising a feed Waterconduit passingthrough said drum of said economizer-section and discharging into saidsteam-generatin -section, means to supply said economizer-section withwater from said stea111-generating-section of said boiler and aconnection between said eeonomizer section and saidstcam-gener-ating-section, whereby steam at and above boiler pressure insaid economizer-seetion is automatically carried over into saidsteam-generating-see tion whenever the supply oi feed water isinsufficient to maintain the temperature of the water in saideconomizer-section below boiling temperatures.

hln a boiler comprising a steanugenei ating-section and aneconomizer-section the combination of means to deliver teeduvaterdirectly to said steam-goaerating-section,

means to pass said leeduvater through the economizer-section to tansterheat from said econo1nizer-section to said teed-water on its passage tosaid steaiii-generating-sectionot' said boiler and to normally keep thetemperature of the water in said economizer-section belowsteam-generating temperatures, means to keep said eeoiiiomizersectionsupplied with purified water from said steam-generating'section of saidboiler andmeans to transfer steam at boilerpressure from saideconomizer-section to said steam-generating-section when the flow ofteed-water through said feedwaterpipe is retarded and the temperature ofthe water in said economiZer-section rises to steamgeneratingtemperatures. I

5. in a steam boiler comprising a steamgenerating-section and aneconomizer-section having upper and lower drums, the combinationot ateed-water supply pipe, a coil in the upper drum of said.economizersection to one end of which said supply pipe is connected, apipe connected to the 0pposite end of said coil and extending to anddischarging into said steam-generating-section of said boiler means toadmit water from said generator-section to said econo mizer-sectiou, a aconduit connecting the space above the water in thesteam-generating-section with the space above the water in the saideconomizer-section, and a check valve in said conduit operative topermit the How of steam from said economizer-section to saidsteam-generating-section, and to prevent the flow of steam from saidsteam-generating-section to said economizen section.

In a boiler comprising a steam-generating-section and aneconomizer-section, the combination therewith of means to deliverteed-water directly to said steam-generating-section means to pass saidfeed-water throu h said economizer-section to transfer heat rrom saideconomizer-section to said feed-water on its passage to saidsteam-generatingsection of said boiler and to normally keep thetemperature of the water in said economizer-section belowsteam-generating temperatures, means to introduce water from thesteamgenerating-section of said boiler into said economizer-section tocompensate for any loss of water contained in said economizer-sectionand automatic means to permit the escape of steam generated in theeconomizer-section of said boiler when the flow of feed-water isinsuflicient to keep the temperature of the water in saideconoinizer-section below boiling temperatures and the pressure of thesteam in said economizer-section is substantially at boiler pressure.

7. In a boiler comprising a steam-generating-section and aneconomizer-section, the combination therewith of a teedavater pipeconnected directly to said steam-generatingsection said pipe passingthrough said economizensection to transfer heat from saideconomizer-section to said feed-water on its passage to saidgenerating-section and to normally keep the temperature of the water insaid economizer-section below boiling temperatures, means to introducewater from said steam-generating-section into said economizer section tocompensate for any loss 01" water in said economizer-section, a pipeconnecting the upper partof said economizensection with the upper partof said steam-generating section, and a check-valve in said pipe toautomatically permit transfer of steam generated in saideconomizer-s-ection to said steam-generating-section through said pipewhen the flow oi feed-water through said feed pipe is in suflicient tomaintain the temperature of the water in said economizer-section belowsteam-generating temperatures and the pressure of steam in saideconomizer-section is substantially the same as that in saidsteamgenerating-section.

In witness whereof, I have hereunto set my hand this 31st day of March,1923.

i JOSIAH H. ROHRER.

